Swiveling work machine

ABSTRACT

A swiveling work machine includes a swivel deck, an engine and an operator&#39;s seat which are mounted on the swivel deck and a protector for the operator&#39;s seat mounted erect on the swivel deck. The swivel deck mounts, at a rear portion thereof, a support frame having four post portions disposed around the engine. Two rear post portions of the support frame have upper ends thereof connected via a rear beam member. The rear beam member includes an attaching portion for the operator&#39;s seat protector to which portion the protector is attached.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a swiveling work machine such as abackhoe.

2. Description of the Related Art

According to a conventional machine of the above type, an engine ismounted at a rear portion of a swivel deck and a radiator is disposed oneither right or left side of the engine. And, across and over thesecomponents, there is disposed a support frame which mounts therein anair cleaner and a muffler (see e.g. Japanese Patent Application “Kokai”No. 11-81378).

There is also known a construction wherein a support frame having arectangular shape in its plan view is mounted forwardly of an engine,the support frame supports an operator's seat and right and leftimplements controllers, and a canopy (an example of an “operator's seatprotector”) is attached to a rear portion of the support frame (see e.g.Japanese Patent Application “Kokai” No. 9-195316).

An operator's seat protector is known also from Japanese PatentApplication “Kokai” No. 8-184075, which comprises a four-postconstruction having four post portions disposed at front and rearportions of a frame of a swivel deck.

In the case of the Japanese Patent Application “Kokai” No. 11-81378mentioned first above, the support frame comprises a three-postconstruction having two front post portions and one rear post portion.This frame has only one beam at the fore and aft center thereof. Hence,this is not provided as a high-strength frame construction. In the caseof the support frame known from the Japanese Patent Application “Kokai”No. 9-195316 mentioned second above, the frame has four post portionsand has a rectangular shape in its plan view. Hence, this is a frameconstruction sturdy enough to support the operator's seat and the rightand left implement controllers. However, this construction does notcontribute significantly to attaching strength of the operator's seatprotector.

In the case of the Japanese Patent Application “Kokai” No. 8-184075method third above, the front and rear post portions of the four-posttype operator's seat protector are affixed directly to the swivel deckframe, the rear post portions of the protector not being supported toany other support frame on the swivel deck.

That is, with these conventional techniques, in disposing the operator'sseat protector in the vicinity of the engine in order to form the swiveldeck compact, it is difficult to support the operator's seat protectorwith greater strength.

In view of the above, the present invention has been made to provide aswiveling work machine capable of solving the above-described problemsof the conventional techniques.

Namely, a primary object of the present invention is to provide aswiveling work machine which is capable of increasing the strength ofthe support frame, mounting the operator's seat protector with greaterstrength and forming an upper structure of a swivel deck compact.

SUMMARY OF THE INVENTION

For accomplishing the above-noted object, according to the presentinvention, a swiveling work machine comprises:

a swivel deck;

an engine and an operator's seat which are mounted on the swivel deck;and

a protector for the operator's seat mounted erect on the swivel deck;

wherein the swivel deck mounts, at a rear portion thereof, a supportframe having four post portions disposed around the engine;

two rear post portions of the support frame have upper ends thereofconnected via a rear beam member; and

said rear beam member includes an attaching portion for the operator'sseat protector to which portion the protector is attached.

With the above-described construction, by using the support frame whichis constructed as a high-strength frame of a four-post type, theoperator's seat protector can be firmly attached. Further, as thisoperator's seat protector is mounted erect adjacent the engine, theupper structure of the swivel deck can be formed compact. Preferably,this support frame has a rectangular shape in plan view.

According to one preferred embodiment of the present invention, theoperator's seat protector is constructed as a four-post type havingright and left front post portions and right and left rear postportions, with the right and left rear support post portions beingattached to said attaching portion, said right and left front postportions being attached to right and left front portions of the swiveldeck.

With the above construction, the four-post type operator's seatprotector can be attached even more strongly by using the support framefor supporting/attaching the right and left rear post portions and usingthe right and left front portions of the swivel deck forsupporting/attaching the front post portions.

Preferably, the operator's seat protector further includes a pair ofright and left upper beam portions which connect upper ends of saidrespective front post portions with upper ends of said respective rearpost portions and mount a roof member thereon, a front lower connectingportion for connecting lower portions of the right and left front postportions, and a rear lower connecting portion for connecting lowerportions of the right and left rear post portions; and at said rearlower connecting portion, there is provided an attaching bracket to beattached to said attaching portion. In the case of the operator's seatprotector having the above construction, the right and left front postportions are interconnected at the lower portions thereof by the frontlower connecting portion, and the right and left rear post portions areinterconnected at the lower portions thereof by the rear lowerconnecting portion. Hence, the frame structure of the protector per secan be formed sturdy.

Preferably, said rear lower connecting portion, the right and left rearpost portions and respective latter halves of the right and left upperbeam portions of the operator's seat protector are formed by bending asingle pipe; a former half of said each upper beam portion and said eachfront post portion are formed of a single pipe, respectively; and theformer half and the latter half of said each upper beam portion isconnected via a connecting member. With this construction, the rearframe structure portion of the operator's seat protector can be formedas a structure free from welded portions, hence capable of avoidingstress concentration. Also, the front side of the protector can bemanufactured easily.

Still preferably, the operator's seat is mounted at an upper portion ofthe support frame; said rear lower connecting portion of the operator'sseat protector is disposed rearwardly of the operator's seat; and alower portion of at least one of the rear post portions extends from therear side of the driver's seat to a lateral side thereof. With thisconstruction, intermediate portions of the right and/or left rear postportions of the operator's seat protector can be utilized for providingprotection on the lateral sides of the driver's seat and providing e.g.handrails for the operator.

According to one preferred embodiment of the present invention, aradiator is disposed on either right or left side of the support frame;an air cleaner and a muffler are mounted inside the support frame; andthe swivel deck includes a support portion to which the support frame isdetachably attached from above the engine.

With this construction, the attachment and detachment of the supportframe and the operator's seat protector relative to the swivel deck canbe carried out easily. Further, the air cleaner and the muffler can beassembled in advance with the support frame, independently of the swiveldeck which mounts the engine. Therefore, the mounting operations of thesupport frame and other vehicle components inside the engine room can becarried out very easily.

Preferably, the support frame includes, at a front upper portionthereof, an attaching portion for the operator's seat and includes also,at a rear upper portion thereof, said attaching portion. With this, theattaching portions for the operator's seat and the operator's seatprotector can be easily formed and the seat and the protector can besupported reliably also.

Still preferably, the support frame includes, at right and left upperportions thereof, attaching portions for right and left implementcontrollers. With this construction, the right and left implementcontrollers can be attached to and assembled with the support frame inadvance. Hence, the rear upper portion of the swivel deck can beassembled very easily.

Still preferably, the support frame includes a support stay projectingfrom a lateral upper portion thereof to be connected with an upperportion of the radiator. With this construction, the radiator can besupported easily and reliably.

Further and other features and advantages of the invention will becomeapparent upon reading the following detailed description of thepreferred embodiments thereof with reference to the accompanyingdrawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a left-front perspective view showing an entire swiveling workmachine according to a first embodiment of the present invention,

FIG. 2 is a right-front perspective view of the machine,

FIG. 3 is a left-rear perspective view of an upper structure of theswiveling work machine,

FIG. 4 is a right-rear perspective view of the upper structure,

FIG. 5 is a front view of a swivel deck,

FIG. 6 is a plan view of the swivel deck,

FIG. 7 is a left side view of the swivel deck,

FIG. 8 is a right side view of the swivel deck,

FIG. 9 is a rear view in section of the swivel deck,

FIG. 10 is a plan view showing a cover unit of the swivel deck,

FIG. 11 is a plan view showing components mounted on the swivel deck,

FIG. 12 is a side view in section showing an inner construction of theswivel deck,

FIG. 13 is an exploded, left-front perspective view of mountingconstructions of the swivel deck for mounting an operator's seat and acanopy,

FIG. 14 is a perspective view showing the components mounted on theswivel deck,

FIG. 15 is a perspective view showing relationship between a supportframe and right and left implement controllers,

FIG. 16 is a left-front perspective view showing the left implementcontroller and its vicinity,

FIG. 17 is a right-front perspective view showing the left implementcontroller and its vicinity,

FIG. 18 is a left-rear perspective view showing the left implementcontroller and its vicinity,

FIG. 19 is a plan view in section showing adjacent portions of a hoodcover and a side cover,

FIG. 20 is a plan view in section showing a pivot portion of the hoodcover,

FIG. 21 is a perspective view of the support frame,

FIG. 22 is a perspective view of a swiveling work machine according to asecond embodiment of the present invention, showing its operator's seatprotector,

FIG. 23 is a side view of the operators seat protector shown in FIG. 22,

FIG. 24 is a front view of the operator's seat protector,

FIG. 25 is a plan view of the operator's seat protector, and

FIG. 26 is an enlarged view of principal portions, showing an attachmentconstruction for the operator's seat protector.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Preferred embodiments of a swiveling work machine relating to thepresent invention will be described in details with reference to theaccompanying drawings.

First Embodiment

In FIGS. 1 through 12, numeral 1 denotes a standard or rearsmall-swiveling type backhoe as an example of a swiveling work machine.This backhoe 1 includes a pair of crawler traveling units 35, an upperstructure 36 having a swivel deck 2, an excavator 37 mounted on theswivel deck 2 and a dozer implement 42 provided forwardly of the crawlertraveling units 35.

Each crawler traveling unit 35 includes a drive wheel and a driven wheelrotatably supported to front and rear portions of a right or left sideframe 38 a of a track frame 38, a plurality of free wheels disposedbetween the drive and driven wheels and a crawler 39 formed of rubber oriron entrained about these wheels, with the drive wheel being driven torotate by a traveling drive source such as a right or left travelingmotor 40.

The track frame 38 supports the right and left side frames 38 a withallowing mutual displacement therebetween along a right/left directionby means of a hydraulic cylinder. Hence, these right and left crawlerunits 35 are constructed as an inter-track distance variable type whichallows increase or decrease of the inter-track distance between theright and left tracks thereof.

When the crawler traveling units 35 are set to the largest inter-trackdistance, a distance L1 from a swivel axis X (shown in FIGS. 6, 7 and11) to the outer side of the right/left crawler traveling unit 35 underthis condition is substantially same as or slightly longer (by e.g.about 10%) than the maximum radius of the swivel deck 2.

On the other hand, when the crawler traveling units 35 are set to thesmallest inter-track distance, a distance L2 from the swivel axis X tothe outer side of the right/left crawler traveling unit 35 under thiscondition is substantially same as or slightly longer (by e.g. about10%) than a distance from the swivel axis X to each right or left sideface of the swivel deck 2 which assumes a forward orientation.

The track frame 38 mounts thereon the swivel deck 2 via a swivel bearing41. The swivel deck 2 can be swiveled to the right or left about theswivel axis X by means of a swivel motor 44. To the front portion of thetrack frame 38, the dozer implement 42 is vertically pivotally attachedvia a dozer cylinder 43.

In FIGS. 1-14, the swivel deck 2 mounts thereon such components as anengine 3, a radiator 5, a hydraulic pump 21 driven by the engine 3, aworking fluid tank 22, a fuel tank 23, a cover unit 9 covering thesecomponents, an operator's seat 12 and right and left implementcontrollers 14, 15 which are disposed upwardly of the cover unit 9, anda traveling controller 19 disposed forwardly of the operators seat 12,etc. These components together constitute the upper structure 36.

A portion of the swivel deck 2 forwardly of the operator's seat 12 isconstructed as an operator's access step 45. Also, at a front portion ofthe swivel deck 2, there is attached a swing bracket 48 of the excavator37 via a receiving bracket 46, with the bracket 48 of the excavator 37being pivotable about a vertical shaft 47.

In the excavator 37, the swing bracket 48 supported to the receivingbracket 46 via the vertical shaft 47 is pivotable to the right or leftby means of a swing cylinder. To this swing bracket 48, respective baseends of a boom 49 and a boom cylinder 50 are pivoted via horizontalshafts to be lifted up/down. To a leading end of the boom 49, an arm 51is pivoted to be vertically pivotable by an arm cylinder 52. To aleading end of the arm 51, a bucket (implement) 53 is pivoted to beoperable by a bucket cylinder 54 for a scooping/dumping operation.

The receiving bracket 46, as shown in FIGS. 6, 7 and 10-14, projectsforwardly from the front face (extreme front end) of the swivel deck 2on the front side of the traveling controller 19. The travelingcontroller 19 and the operator's seat 12 are disposed with an offset toone of right and left sides (offset to the left side) from a centerlineextending through the swivel axis X, whereas the receiving bracket 46 isdisposed with an offset to the other of the right and left sides (offsetto the right side).

The plan view shape of the swivel deck 2 is substantially front-squareand back-round shape having a straight front face, parallel right andleft side faces and an arcuate rear face. A distance from the swivelaxis X of the swivel deck 2 to the leading end of the receiving bracket46 or to the vertical shaft 47 is substantially same as or shorter thana distance from the swivel axis X to the rear end of the swivel deck 2.Preferably, these distances should be substantially same as or smallerthan the distance from the swivel axis X to the outer end of the crawler39 when the crawler traveling units 35 are set to the largestinter-track distance.

As this swiveling work machine 1 is compact, the area of the swivel deck2 is extremely small, with the front face of the operator's seat 12being disposed at substantially same position as the swivel axis X.

As shown in FIGS. 9-14, referring to the construction of the swivel deck2, on a base plate 2A acting as a base of the deck, there are disposederect a pair of right and left vertical walls 57 flared rearward fromthe receiving bracket 46 disposed forwardly. At an intermediate portionof the base plate 2A, there is disposed erect a partitioning wall 58extending across the right and left vertical walls 57. Further, at arear portion of the base plate 2A, there is disposed erect a receivingwall 59 connected to respective rear ends of the right and left verticalwalls 57. At an intermediate potion and a peripheral portion, there aredisposed erect attaching stays for attaching various vehicle componentsand a periphery cover on the base plate 2A.

At a rear potion of the base plate 2A, the engine 3 is mounted with alateral orientation as being fitted among the partitioning wall 58 andthe right and left receiving walls 59. And, across and over this engine3, there is mounted a support frame 4 having four support posts or postportions. At a rear end of the base plate, there is mounted an arcuatecounter weight 56 attached via the right and left receiving walls 59.

Referring to the configuration of the support frame 4, an upper portionand a front portion thereof are formed rectangular, whereas right andleft side portions and a rear portion thereof are formed portal. Frontright and left post portions 4A, 4B are connected at lower portionsthereof by an attachment plate 60A and are detachably bolt-fixed viathis attachment plate 60A to an upper face of the partitioning wall 58.

Rear right and left post portions 4C, 4D of the support frame 4 alsoinclude an attachment plate 60B at lower ends thereof and are detachablybolt-fixed via the plate 60B to the right and left receiving walls 59.

To an upper portion of the partitioning wall 68, a plate member isaffixed for forming a support portion 18A for receiving and supportingthe attachment plate 60A. Similarly, to upper portions of the right andleft receiving walls 59, a plate member is affixed for forming a supportportion 18B for receiving and supporting the attachment plate 60B. Withthese support portions 18A 18B, the support frame 4 can be attached toand detached from the base plate 2A from above, with the base plate 2Amounting the engine 3 thereon. As the vehicle components present aroundthe engine 3 are supported to the support frame 4, there is no obstaclewhich may interfere with the fitting of the support frame 4 over theengine 3.

The support frame 4 includes a pair of right and left portal memberseach comprising an L-shaped plate and a strip member affixed thereto,thereby to form the front right and left post portions 4A, 4B, the rearright and left post portions 4C, 4D and upper right and left sideportions 4E, 4F. The attachment plate 60A is affixed to front lower endsof the right and left post portions 4A, 4B of the two portal members.Also, a front beam member (front upper beam) 61 comprising a strip plateor a strip plate bent arcuate in its cross section is affixed to theupper ends of the front right and left post portions 4A, 4B. Further, arear beam member (rear upper beam) 62 formed of a thick plate is affixedto the rear upper portions of the right and left side portions 4E, 4F.Hence, the support frame 4 as a whole forms an outer frame of the engineroom.

The front beam member 61 forms an attaching portion 61 a for attaching apivot member 63 for supporting the front of the operator's seat 12 to bepivotable about a horizontal axis. The rear beam member 62 forms anattaching portion (post portion attaching portion) 62 a for attaching apost portion 13A of a canopy type operator's seat protector 13.Incidentally, this operator's seat protector can be constructed as aROPS (rollover protection system) also.

The operator's seat 12 is constructed such that its rear portion ismounted and supported to the right and left side portions 4E, 4F or therear beam member 62. A substantially entire area of the seat 12 islocated above the support frame 4 and the engine 3 and the entire loadthereof is supported by the support frame 4. Since the support frame 4is constructed as the four-post type, this frame can provide highstrength and can firmly support the operator's seat 12 and theoperator's seat protector 13.

When the operator's seat protector 13 is attached to the attachingportion 62 a, its lower portion is located adjacent the engine 3, inparticular, rearwardly of the engine 3 disposed at the extreme rear end.Since the operator's seat protector 13 is located adjacent theoperator's seat 12 of course, the upper structure of the swivel deck 2including the operator's seat protector 13 can be formed short in thefore and aft direction, hence, formed compact.

To the support frame 4, a fixed cover 6 is fixed for covering the frontface and the upper face of the frame 4. This fixed cover 6 is formed ofan L-shaped (in side view) plate member (or two plates including a frontplate and an upper plate). And, the cover 6 is bolt-fixed to the frontright and left post portions 4A, 4B, the front beam member 61 providedin the upper face and the right and left side portions 4E, 4F of thesupport frame 4 and the cover is engaged with the rear beam member 62 tobe fastened therewith to the operator's seat protector 13.

An upper portion of the fixed over 6 is retracted into the support frame4 and an upper inspection window 90 is formed at this retracted portion.This upper inspection window 90 is closed with an upper lid. A frontportion of the cover 6 is also retracted into the support frame 4 and afont inspection window 91 is formed at this retracted portion. Thisfront inspection window 91 is closed with a front cover.

In FIGS. 9-12 and 21, the right side portion 4F of the support frame 4includes an upper wind guide plate 29A inclined downwardly to the rightouter side. The right post portion 4B includes a front wind guide plate29B inclined rearwardly to the right outer side. So that, hot air from aradiator fan is guided downwardly toward to right rear side.

Further, between the fixed cover 6 and the right post portion 4B of thesupport frame 4 and also between the cover 6 and the right side portion4F thereof, there is interposed a seal member 28 for preventing leakageof the hot air or noise toward the operator's seat 12 through the gapstherebetween before the air is guided to the upper wind guide plate 29Aand the front wind guide plate 29B.

The two guide plates (i.e. the upper wind guide plate 29A and the frontwind guide plate 29B) are formed of e.g. sheet metal. Instead of theseplates or in addition to these plates, a seal member may be interposedbetween the right edge of the fixed cover 6 and the members present onthe side thereof, for preventing leakage of hot air toward theoperator's seat 12.

Inside the support frame 4, within the space delimited with the engine3, an air cleaner 10, a muffler 11, an oil filter 92, a reserve tank 93and other vehicle components are disposed and these are attached to thesupport frame 4 per se. The support frame 4 assembled in advance withsome of these components can be attached to and detached from the baseplate 2A from above the engine 3.

On one of the right and left side (right side) of the engine 3, there isdisposed the hydraulic pump 21 driven by the engine and on the otherside of the engine 3 (left side, on the side of the operator'sentrance/exit), the radiator 5 and the radiator fan are disposed. On theouter side of the radiator 5, such components as an oil cooler 64, abattery 65, etc. are disposed. These components are mounted on the baseplate 2A, separately from the support frame 4.

The radiator 5 is constructed as an air intake type and mounted on thebase plate 2A adjacent the left side face of the support frame 4. And,an upper portion of the radiator 5 is fixedly connected via a bracket16B to a support stay 16A projecting to the outer side from the leftside portion 4E.

Further, as shown in FIGS. 14-18, a plurality of stays 66 formed ofplates or bars project to the outer side from the left side portion 4E.Via these stays 66, a base 14 a of the left implement controller 14 isfixed. The base 14 a is disposed on the left outer side of the radiator5 and pivotally supports via a pivot shaft 70 a a lower pivot 70 of aunit frame 69 of the left implement controller 14.

An upper portion of the unit frame 69 is formed as a box-like memberelongated in the fore and aft direction and forms a lower pivot portionformed narrow along the fore and aft direction and supported to thepivot shaft 70 a. On the pivot shaft 70 a, there is engaged an urgingmeans (coil spring) for urging the left implement controller 14 toward aretracted posture raised from a control posture.

Referring to the left implement controller 14, a pilot valve 72Loperable by a left control lever 71L is attached to an upper portion ofthe unit frame 69, and there is provided a posture changing means 74operable by a posture changing lever 73.

The posture changing lever 73 is fixed to an end of a lever shaft 73 apivoted to an upper portion of the box of the unit frame 69. To theother end of the lever shaft 73 a, there is fixed a cam 77 having a camgroove 77 a. This cam groove 77 a of the cam 77 is engaged with a camfollower 78 provided on the base 14 a.

At a deep portion of the cam groove 77 a, an engaging recess 77 b isformed. In operation, in response to a shift of the left implementcontroller 14 from the retracted posture (shown with a solid line inFIGS. 6 and 7) to a control posture (shown with a dashed line in FIGS. 6and 7), the unit frame 69 is pivoted about the pivot shaft 70 a so thatvia the posture changing lever 73, the cam 77 is moved relative to thecam follower 78 and the cam follower 78 is moved to the deeper side ofthe cam groove 77 a, then, the engaging recess 77 b comes intoengagement with the cam follower 78, thereby to retain the leftimplement controller 14 at the control posture. Under this controlposture, the engagement between the engaging recess 77 b and the camfollower 78 is maintained by the urging member 17 provided to theposture changing lever 73.

For changing the control posture to the retracted posture, the posturechanging lever 73 is pivoted upward against the urging force of theurging member 17. With this, the engaging recess 77 b is disengaged fromthe cam follower 78, thereby to release the posture maintenance by theposture changing lever 73. As the operator further pivots the posturechanging lever 73, the left implement controller 14 is pivoted upwardtogether therewith.

The urging member 17 which provides the rotational force to the cam 77for engaging the engaging recess 77 b with the cam follower 78 isdisposed between the posture changing lever 73 and a rear portion of thebox-like upper portion of the unit frame 69. As the urging member 17 isdisposed not along the vertical direction, but along the fore and aftdirection at the box-like upper portion of the unit frame 69, the lowerpivot 70 is formed narrow along the fore and aft direction to bedisposed inside a side cover 8.

The side cover 8 is disposed on the left outer side of the radiator 5,the oil cooler 64 and the battery 65 for covering these. The side cover8 is detachably attached to the base plate 2A and the support frame 4.This side cover 8 has an ambient air inlet window and engages with alower portion of the left implement controller 14 for covering the pivotshaft 70 a and the lower pivot portion 70.

As shown in FIGS. 3, 5-7, 10 and 12, the side cover 8 is open at itsupper portion for accommodating the lower pivot 70 of the left implementcontroller 14 therein and covering this lower pivot 70. Further, as theleft implement controller 14 is disposed as close as possible to theleft side face of the swivel deck 2, the swivel deck 2 is formed compactin the right/left direction.

The side cover 8 is disposed such that its front face 8 a is disposedsubstantially flush with the front face 6 a of the fixed cover 6. And,this cover 8 is supported via a vertical shaft (hinge) 79 to the leftfront post portion 4A (or the partitioning wall 58 raised from the baseplate 2A) of the support frame 4, so that the cover can be pivotallyopened/closed. Further, a rear end of the side cover 8 is disposedadjacent the left end of a hood cover 7.

Further, in this left implement controller 14, the unit frame 69includes a cover 76. And, the controller 14 with this cover 76 isarranged such that under the retracted posture, its front face (thefront face of the left implement controller 14) 76 a is disposedsubstantially flush with the front face 8 a of the side cover 8 and thefront face 6 a of the fixed cover 6 (i.e. at a same position in the foreand aft direction). And, a front face 12 a of the operator's seat 12 toois disposed substantially flush with these.

Incidentally, any one or two of the fixed cover 6, the side cover 8, theoperator's seat 12 and the left implement controller 14 may be displacedin the fore and aft direction relative to the others. In doing this,rearward displacement is preferred to forward displacement. If the frontface 8 a of the side cover 8 and the front face 6 a of the fixed cover 6which comprise erect walls on the back side of the operator's accessstep 45 are disposed substantially flush each other, the operator'saccess step 45 can have a large area for facilitating the operator'spassage or movement from an entrance/exit 20 to the operator's seat 12.

As shown in FIGS. 3, 12, 19 and 20, the right rear post portion 4D ofthe support frame 4 is disposed on the right rear side of the engine 3opposite to the side of the entrance/exit 20 and the radiator 5. Thisright rear post portion 4D pivotally supports a right end of the hoodcover 7 via a vertical shaft (hinge) 82, so that the right end of thecover can be pivotally opened/closed.

Whereas, the left end (free end edge) of the hood cover 7 is disposedadjacent a rear end (free end edge) of the side cover 8, so that theleft end can be superposed thereon from the outer side via an edge sealmember 32. By locking the cover with a lock provided between this coverand the counter weight 31 provided at the rear end of the swivel deck 2,inadvertent opening of the side cover 8 can be prevented also.

The plan view shape of the hood cover 7 is an arcuate shapeapproximating the rear shape of the counter weight 31. And, along itsperipheral edge, an edge seal member 32 is provided for sealing gapsbetween the rear end of the side cover 8, the rear beam member 62 of thesupport frame 4 and the counter weight 31, so as to prevent leak of hotair and/or noise inside the engine room through the hood cover 7.

The hood cover 7 is pivoted at its right end to the support frame 4 andthe side cover 8 is pivoted at its front face to the support frame 4,respectively. That is to say, these covers can be pivotally opened inbiparting manner via the respective vertical shafts on the adjacent sideand on the opposite side. Therefore, by opening these covers in thebiparting manner as shown in FIG. 3, the rear portions of the engine 3and the radiator 5, the side portions and upper portions of the radiator5, the oil cooler 64 and the battery 64 can be exposed, so thatmaintenance operations of the engine 3 and most of other vehiclecomponents present inside the engine room can be carried out easily.

Further, as the hood cover 7 is constructed as a horizontally open type,this cover can be opened wide without being interfered with by theoperator's seat protector 13 disposed upwardly of this cover. Also, thishood cover 7 can be opened independently of the side cover 8, i.e.without necessitating simultaneous opening of the side cover 8.

On the right side of the engine 3, there is disposed the hydraulic pump21 to which the rotational power is transmitted from the crank shaft ofthe engine 3. Forwardly of this hydraulic pump 21, there is disposed theworking fluid tank 22 and forwardly of this working fluid tank 22, thefuel tank 23 is disposed.

On the right side portion 4F of the support frame 4 and upwardly of theupper wind guide plate 29A, there is provided a box 81 of the rightimplement controller 15. At a front portion of this box 81, there isprovided a pilot valve 72R having a right control lever 71R. The rightside face of the box supports two control levers 84, 85 and at a rearportion of the box, an electric unit 30 is accommodated. Hence, adverseeffect of the hot air current to the electric unit 30 is avoided bymeans of the upper wind guide plate 29A which guides the hot air frominside the engine room to the outside. Numeral 83 denotes a box coverfor the box 81.

The working fluid tank 22 and the fuel tank 23 are disposed on the rightside of the operator's seat 12 and are covered with a tank cover 24. Thefront wind guide plate 29B is disposed rearwardly of the working fluidtank 22 for avoiding adverse effect of the hot air current to theworking fluid tank 22.

The tank cover 24 includes an inner wall plate (side wall) 24A on theside of the operator's access step 45 and an outer cover 24B forcovering upper and right side faces of the working fluid tank 22 and thefuel tank 23 and the front face of the fuel tank 23.

The inner wall plate 24A is affixed to the base plate 2A and the rightpost portion 4B of the support frame 4 or the right end of the fixedcover 6 and is disposed to project forwardly from the support frame 4,so as to cover the left side faces of the working fluid tank 22 and thefuel tank 23.

The outer cover 24B covers the upper faces, the right side faces and thefront and rear faces of the working fluid tank 22 and the fuel tank 23.This cover 24B defines a fuel inlet opening at a position correspondingto an upper portion of the fuel tank 23, which is closed with a lid 24C.The outer cover 24 b defines, at a right side portion thereof, amultiple-aperture type air exhaust portion 24D.

The faces of the inner wall plate 24A and the fuel tank 23 on the sideof the operator's access step 45 are inclined to the right side asextending forwardly, so that the front space above the operator's accessstep 45 is formed large for facilitating the operator's operation of thetraveling controller 19.

Further, a side face 22 a of the working fluid tank 22 on the side ofthe operator's access step 45 is inclined to the right side as extendingrearward, so as to form, between the inner wall plate 24A and thesupport frame 4, a substantially triangular space 26 (shown in FIG. 10)extending wider rearward. Within this space 26, hydraulic pipes and/orharnesses are arranged. With this concentrated arrangement of thesecomponents, the pipe arranging operation and maintenance operation arefacilitated.

At a front upper portion of the base plate 2A of the swivel deck 2,there is mounted a control valve assembly 94 comprising a plurality ofvalves connected to each other along the right/left direction. Theperimeter of the base plate 2A is covered with a side cover 99. And, theoperator's access step 45 disposed upwardly thereof is formed byattaching a step plate on the base plate 2A and then disposing a mat onthe top surface of the step plate.

The traveling controller 19 mounted at the front portion of the swiveldeck 2 includes right and left traveling control levers 95L, 95R andvarious control pedals disposed at the feet of these levers, including aservice port pedal 96, a swing pedal 97, etc. Further, a front handrail98 is provided forwardly of these pedals.

Second Embodiment

FIGS. 22-26 show a second embodiment of a backhoe (an example of“swiveling work machine”) 1 relating to the present invention. Theprincipal difference from the foregoing first embodiment lies in theconstruction of the operator's seat protector 13. Therefore, thefollowing discussion is focused on this construction.

That is, the operator's seat protector 13 in this embodiment isconstructed as a four-post type having right and left front postportions 13AF and right and left rear post portions 13AR. The right andleft rear post portions 13AR are attached to the attaching portion 62 aof the support frame 4, whereas the right and left front post portions13AF are attached to the right and left front portions of the swiveldeck 2.

More particularly, this operator's seat protector 13 includes the rightand left front post portions 13AF, the right and left rear post portions13AR, a pair of right and left upper beam portions 13AU which connectupper ends of the right and left front post portions 13AF with upperends of the right and left rear post portions 13AR and mount a roofmember 86 thereon, a front lower connecting portion 13AD for connectinglower portions of the right and left front post portions 13AF, and arear lower connecting portion 13AH for connecting lower portions of theright and left rear post portions 13AR.

In this operator's seat protector 13, the rear lower connecting portion13AH, the right and left rear post portions 13AR and respective latterhalves of the right and left upper beam portions 13AU are formed bybending a single pipe. A former half of each right/left upper beamportion 13AU and each right/left front post portion 13AF are formed of asingle pipe, respectively. And, the former half and the latter half ofeach right/left upper beam portion 13AF is connected via a connectingmember 100 formed of e.g. a round bar.

That is, in the rear half portion of the operator's seat protector 13,at a center portion of the single pipe, the rear lower connectingportion 13AH is formed, and from opposed ends of this rear connectingportion 13AH, the pipes extend with a forward upward inclination to formthe lower portions of the right and left rear post portions 13AR. Then,the pipes are bent with substantially straight upward inclination fromthe upper ends of the lower portions of the right and left rear postportions 13AR to form the upper portions of the right and left rear postportions 13AR. Then, from these upper ends of the right and left rearpost portions 13AR, the pipes are bent forwardly to form the latterhalves of the right and left upper beam portions 13AU. Hence, this rearframe structure portion of the operator's seat protector 13 is formedwithout any welded portions, hence, effectively avoiding concentrated orlocal stress application.

Further, in the front half portion of the operator's seat protector 13,from the former halves of the right and left upper beam portions 13AU,the upper portions of the right and left front post portions 13AF extendwith a slightly forward and downward inclination. And, lower portions ofthe right and left front post portions 13AF are formed substantiallyvertical. And, the former half of each right/left upper beam portion13AU and the right/left front post portion 13AF corresponding therewithare formed of a pipe. And, these pipes are connected to each other viathe front lower connecting portion 13AD to be integral with each other.Hence, the front portion of the operator's seat protector 13 too can bemanufactured easily.

As described above, the front half portion and the rear half portion ofeach right/left upper beam portion 13AU is connected to each other bythe insertion of the connecting member 100 therebetween. In this, thefront half portion and the rear half portion of the upper beam portion13AU may be welded respectively to the connecting member 100. Instead,these portions may be detachably connected to each other with insertionof a pin, so that the operator's seat protector may be disassembledalong the fore and aft direction.

At the rear lower connecting portion 13AH, there is provided anattaching bracket 87 to be attached to the attaching portion 62 a of thesupport frame 4. When the attaching bracket 87 is attached to theattaching portion 62 a, the lower portions of the rear post portions13AR are located upwardly and rearwardly of the engine 3 and theirvertical intermediate portions are located laterally of the operator'sseat 12. In this way, the sturdy support of the operator's seatprotector 13 by the support frame 4, the compact arrangement of theupper structure of the swivel deck 2, the protection of the operator'sseat 12 and the co-utilization of the construction as a handrail for theoperator to be seated at the operator's seat 12 can be achieved.

At the lower portions of the forwardly upwardly inclined right and leftrear post portions 13AR, there is provided a rear connecting member 88having an arcuate shape in plan view and connecting the right and leftsides. This rear connecting member 88 provides protection to the rearface of the operator's seat 12. The rear ends of this back connectingmember 88, the rear lower connecting portion 13AH and the room member 86are substantially aligned with each other in the fore and aft direction,thus forming the rearmost portion of the upper section of the implementattaching unit.

At vertically intermediate portions of the right and left front postportions 13AF, there are connected a pair of upper and lower frontconnecting members 89 forming front handrails. These upper and lowerfront connecting members 89 are also connected to each other viavertical members. On the left front post portion 13AF, an upper handrail101 is attached.

The lower ends of the right and left front post portions 13AF areconnected via the front lower connecting portion 13AD as describedabove. This front lower connecting portion 13AD includes a pair of lowerflat plates 102 affixed to the lower ends of the right and left frontpost portions 13AF and a vertical plate 103 affixed to upper faces ofthe right and left lower flat plates 102 and the side faces of the rightand left front post portions 13AF. The lower flat plates 102 are mountedon a plurality of attaching bases 104 formed erect at the front end ofthe base plate 2A and the upper face of the receiving bracket 46, etc.Then, as the right and left lower flat plates 102 and the attachingbases 104 are fastened together by means of bolts 105, the front portionof the operator's seat protector 13 is detachably fixed to the swiveldeck 2.

The right and left upper beam portions 13AU are connected to each otherat front and intermediate portions thereof by means of a plurality offront and rear upper connecting members 106 and connected also at therear portions thereof by means of an upper rear connecting member 107.This upper rear connecting member 107 has an arcuate shape similar tothe rear portion of the roof member 86 projecting rearwardly from theright and left upper beam portions 13AU. The roof member 86 is supportedto the right and left upper beam portions 13AU and the upper rearconnecting member 107 and is bolt-attached to the upper connectingmember 106.

The upper connecting member 106, the upper rear connecting member 107,the upper handrail 101, the front connecting member 89, the rearconnecting member 88, etc. are all formed of pipes or round bars.

The rest of the construction of this embodiment is identical to that ofthe first embodiment. Therefore, description thereof is omitted.

Other Embodiments

The shapes and positional relationships in the fore and aft direction,right/left direction and vertical direction of the respective membersand components used in the foregoing embodiments are best whenconstructed as shown in FIGS. 1-26. However, the invention is notlimited thereto. Various modifications of these members and theirconstructions or combinations thereof would be possible for one skilledin the art.

For instance, the swiveling work machine 1 can be constructed as asuper-small swiveling type having a boom pivoted at the center of theswivel deck 2. The swivel deck 2 and the components and devices mountedthereon can be reversed in their positions in the right/left direction.

The support frame 4 can be constructed as a five-post type or adifferent four-post type having a non-rectangular shape in its plan view(e.g. a trapezoidal shape in plan view).

The hood cover 7 may be constructed as an upper pivotal type. The sidecover 8 may be constructed as a rear-end pivotal type or even as adetachable type.

Moreover, the rear lower connecting portion 13AH, the right and leftrear post portions 13AR, the upper beam portions 13AU and the right andleft front post portions 13AF may be formed of separate members whichare to be welded one after another. Further, the operator's seatprotector 13 may be utilized as a framework for the cabin.

1. A swiveling work machine comprising: a swivel deck; an engine and anoperator's seat which are mounted on the swivel deck; and a protectorfor the operator's seat mounted erect on the swivel deck; wherein theswivel deck mounts, at a rear portion thereof, a support frame havingfour post portions disposed around the engine; two rear post portions ofthe support frame have upper ends thereof connected via a rear beammember; said rear beam member includes an attaching portion for theoperator's seat protector to which portion the protector is attached;the support frame includes, at a front upper portion thereof anattaching portion for the operator's seat to which portion theoperator's seat is attached; the operator's seat protector isconstructed as a four-post type having right and left front postportions and right and left rear post portions, with the right and leftrear support post portions being attached to said attaching portion,said right and left front post portions being attached to right and leftfront portions of the swivel deck, a pair of right and left upper beamportions connect upper ends of said respective front post portions withupper ends of said respective rear post portions and mount a roof memberthereon, a front lower connecting portion for connecting lower portionsof the right and left front post portions, and a rear lower connectingportion for connecting lower portions of the right and left rear postportions; and at said rear lower connecting portion, there is providedan attaching bracket to be attached to said attaching portion.
 2. Theswiveling work vehicle according to claim 1, wherein said rear lowerconnecting portion, the right and left rear post portions and respectivelatter halves of the right and left upper beam portions of theoperator's seat protector are formed by bending a single pipe; a formerhalf of said each upper beam portion and said each front post portionare formed of a single pipe, respectively; and the former half and thelatter half of said each upper beam portion is connected via aconnecting member.
 3. The swiveling work vehicle according to claim 2,wherein the operator's seat is mounted at an upper portion of thesupport frame; said rear lower connecting portion of the operator's seatprotector is disposed rearwardly of the operator's seat; and a lowerportion of at least one of the rear post portions extends from the rearside of the driver's seat to a lateral side thereof.
 4. The swivelingwork vehicle according to claim 1, wherein a radiator is disposed oneither right or left side of the support frame; an air cleaner and amuffler are mounted inside the support frame; and the swivel deckincludes a support portion to which the support frame is detachablyattached from above the engine.
 5. The swiveling work vehicle accordingto claim 1, wherein the support frame includes, at right and left upperportions thereof, attaching portions for right and left implementcontrollers.
 6. The swiveling work vehicle according to claim 5, whereinthe support frame includes a support stay projecting from a lateralupper portion thereof to be connected with an upper portion of theradiator.
 7. A swiveling work machine comprising: a swivel deck; anengine and an operator's seat which are mounted on the swivel deck; anda protector for the operator's seat mounted erect on the swivel deck;wherein the swivel deck mounts, at a rear portion thereof, a supportframe having four post portions disposed around the engine; two rearpost portions of the support frame have upper ends thereof connected viaa rear beam member; said rear beam member includes an attaching portionfor the operator's seat protector to which portion the protector isattached; the support frame includes, at right and left upper portionsthereof, attaching portions for right and left implement controllers;the operator's seat protector is constructed as a four-post type havingright and left front post portions and right and left rear postportions, with the right and left rear support post portions beingattached to said attaching portion, said right and left front postportions being attached to right and left front portions of the swiveldeck, a pair of right and left upper beam portions connect upper ends ofsaid respective front post portions with upper ends of said respectiverear post portions and mount a roof member thereon, a front lowerconnecting portion for connecting lower portions of the right and leftfront post portions, and a rear lower connecting portion for connectinglower portions of the right and left rear post portions; and at saidrear lower connecting portion, there is provided an attaching bracket tobe attached to said attaching portion.
 8. The swiveling work vehicleaccording to claim 7, wherein said rear lower connecting portion, theright and left rear post portions and respective latter halves of theright and left upper beam portions of the operator's seat protector areformed by bending a single pipe; a former half of said each upper beamportion and said each front post portion are formed of a single pipe,respectively; and the former half and the latter half of said each upperbeam portion is connected via a connecting member.
 9. The swiveling workvehicle according to claim 8, wherein the operator's seat is mounted atan upper portion of the support frame; said rear lower connectingportion of the operator's seat protector is disposed rearwardly of theoperator's seat; and a lower portion of at least one of the rear postportions extends from the rear side of the driver's seat to a lateralside thereof.
 10. The swiveling work vehicle according to claim 7,wherein a radiator is disposed on either right or left side of thesupport frame; an air cleaner and a muffler are mounted inside thesupport frame; and the swivel deck includes a support portion to whichthe support frame is detachably attached from above the engine.
 11. Theswiveling work vehicle according to claim 7, wherein the support frameincludes, at a front upper portion thereof, an attaching portion for theoperator's seat and includes also, at a rear upper portion thereof, saidattaching portion for the operator's seat protector.
 12. The swivelingwork vehicle according to claim 7, wherein the support frame includes asupport stay projecting from a lateral upper portion thereof to beconnected with an upper portion of the radiator.